Our work focuses on the thiamine biosynthetic pathway in Salmonella typhimurium. We have currently found two novel metabolic inputs into the synthesis of the pyrimidine moiety of thiamine which was reportedly derived from de novo purine biosynthesis. Our current work focuses on determining the genes and gene products involved in the alternative pyrimidine biosynthetic pathway (APB) we have described. We foresee this work requiring structural determination of various metabolites we isolate from mutants affecting thiamine synthesis. One step in this structural determination will be the NMR spectral determination carried out by NMRFAM.